Messages in this thread Patch in this message | | | Date | Sun, 19 Mar 2006 10:34:21 +0800 | From | Wu Fengguang <> | Subject | [PATCH 08/23] readahead: common macros |
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Define some common used macros for the read-ahead logics.
Signed-off-by: Wu Fengguang <wfg@mail.ustc.edu.cn> ---
mm/readahead.c | 15 +++++++++++++-- 1 files changed, 13 insertions(+), 2 deletions(-)
--- linux-2.6.16-rc6-mm2.orig/mm/readahead.c +++ linux-2.6.16-rc6-mm2/mm/readahead.c @@ -14,6 +14,17 @@ #include <linux/blkdev.h> #include <linux/backing-dev.h> #include <linux/pagevec.h> +#include <linux/writeback.h> +#include <linux/nfsd/const.h> + +/* The default max/min read-ahead pages. */ +#define KB(size) (((size)*1024 + PAGE_CACHE_SIZE-1) / PAGE_CACHE_SIZE) +#define MAX_RA_PAGES KB(VM_MAX_READAHEAD) +#define MIN_RA_PAGES KB(VM_MIN_READAHEAD) +#define MIN_NFSD_PAGES KB(NFSSVC_MAXBLKSIZE/1024) + +#define next_page(pg) (list_entry((pg)->lru.prev, struct page, lru)) +#define prev_page(pg) (list_entry((pg)->lru.next, struct page, lru)) void default_unplug_io_fn(struct backing_dev_info *bdi, struct page *page) { @@ -21,7 +32,7 @@ void default_unplug_io_fn(struct backing EXPORT_SYMBOL(default_unplug_io_fn); struct backing_dev_info default_backing_dev_info = { - .ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE, + .ra_pages = MAX_RA_PAGES, .state = 0, .capabilities = BDI_CAP_MAP_COPY, .unplug_io_fn = default_unplug_io_fn, @@ -49,7 +60,7 @@ static inline unsigned long get_max_read static inline unsigned long get_min_readahead(struct file_ra_state *ra) { - return (VM_MIN_READAHEAD * 1024) / PAGE_CACHE_SIZE; + return MIN_RA_PAGES; } static inline void reset_ahead_window(struct file_ra_state *ra) -- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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